(February 15, 2013) -- Now that she’s going to be the WTA’s No. 1 player on Monday for the first time in more than two years, Serena Williams finally has someone to compete against: Serena Williams.

Williams can aim to break her own record--that of being the oldest woman to ever hold the WTA’s No. 1 ranking--every week in perpetuity, as long as she stays healthy and keeps winning her share of big matches.

The winning has always been easy for the astronomically gifted Williams; the health, however, can be challenging.

With her 3-6, 6-3, 7-5 victory over Petra Kvitova in Doha today, Williams ascended to the top of the WTA’s rankings for the 6th time in her career to reiterate what most of her aspiring peers have already become painfully aware of: When it comes to women’s tennis, there is Serena Williams, almost invincible when she’s at her best, and there is the rest of the field.

Williams’ combined 31-4 record against the rest of the WTA’s top five is clear, unassailable proof of her hegemony at this juncture of her career. Therefore, the only roadblock that could realistically get in the way of Williams and a prolonged, record-breaking stay at No. 1 would be a significant improvement from either Maria Sharapova or Victoria Azarenka or a significant dropoff in Serena’s quality of play.

Considering Williams’ almost preposterous preeminence over Sharapova and Azarenka (She’s a combined 21-3 against the No. 2 and No. 3 players in the world, and her psychological influence over them goes way beyond the one-sided record) it is likely that Serena Williams versus the aging process might be the most intriguing battle on the horizon in WTA circles this season. If Serena can run the table in 2013, it might be the key storyline in 2014, too.

That isn’t to detract from the level of play on the WTA Tour at the moment. The talent base is refreshingly deep, with clusters of diverse, exceptionally talented stars-to-be all over the top 100. Clearly, however, none of them will be able to tackle the enormous mountain of challenges presented by Serena Williams until the 15-time Grand Slam champion starts slowing down of her own accord.

When will that be? Surely Williams, at 31 years and four months of age, is pushing up against her physical prime already. “30 is the new 20” is a cute slogan, and inspiring too, but try spending three hours on a blazing-hot hard court for four or five successive days and tell me which age you’d rather be.

All of which leads us to the burning question at hand: How long can Serena Williams beat back Father Time the way she has always beaten back even her most hellacious competition on the WTA Tour? She’s done a remarkable job already to come back from a near-death experience in early 2011, when a pulmonary embolism and a related hematoma forced her to be hospitalized while she received emergency treatment in L.A. At the time, many wondered if the game would pass her by while she tried to recover from the major blow.

“I never thought I would be here again,” Williams said today, reflecting no doubt on that grim time in her life and breaking down in tears as she spoke. “Oh my gosh I’ve been through so much, and I never thought I would be here.”

But with Williams slashing her way through the competition in 2012 to the tune of 58-4, and milking her newfound, born-again aura, we knew she would be here. Additionally, all signs point to the 15-time Grand Slam champion being "here" for as long as she can stay healthy. Unlike that other Father Time thrasher, Roger Federer (also 31), who has to battle a trio of legends-to-be as he approaches 32, Williams just has to battle her body. The rest should take care of itself.

Even the fans who typically root against the polarizing Williams seem to be pulling for her this time around. They were vociferous in their support for her today in Doha, which might be a sign that they are sympathetic to the rough road that lies ahead for Serena.

“I could hear people cheering for me,” Williams said in her emotional post-match interview, “and I don’t get that all the time, so it was really nice.”

What would be even nicer for Williams, most agree, would be for her to cement her legacy with a sustained run at the top and at least three more Grand Slam titles. That would give her 18, enough to tie her with Chris Evert and Martina Navratilova, the two players who Williams leapfrogged today to become the oldest No. 1 in history.

She’ll have her work cut out for her, but each day when she wakes up and looks in the mirror, she’ll be staring the competition right in the eye.